A long time ago, I took the Sierra Club Basic Mountaineering Training Course (which was since abolished after some lawsuits!).
We practiced the bowline-on-a-coil and belaying someone on flat land, and then we did rock climbing, belaying each other.
I had a gentleman on the climbing end, who shouted "on belay" to which I responded "belay on."
Then he yelled "falling." I was sitting with my feet braced, and I'd practiced holding with my legs instead of my arms, so I was able to keep him from getting hurt. I guess nowadays I could monetize that, if I had it on video.
The risk with the Bowline is that it can work itself loose if it is repeatedly tensioned and loosened. It _definitely_ needs a backup safety knot on the tail.
Or tie it as a double round-turn bowline, with an extra turn for both the "rabbit" going around the tree, and for the hole.
In a previous job I had to constantly take my office master key out of my pocket and put it back. Before long I made a lanyard for it with a brass clip to go on a belt loop and a regular split ring on the other end, both attached with a normal bowline. After a short period, maybe a few weeks to a month, I noticed it loosening up. I retied it with double round-turn bowlines on each end, and it held together like that for years.
We practiced the bowline-on-a-coil and belaying someone on flat land, and then we did rock climbing, belaying each other.
I had a gentleman on the climbing end, who shouted "on belay" to which I responded "belay on."
Then he yelled "falling." I was sitting with my feet braced, and I'd practiced holding with my legs instead of my arms, so I was able to keep him from getting hurt. I guess nowadays I could monetize that, if I had it on video.